WO2024149639A1

WO2024149639A1 - Adjustable transducer elements

Info

Publication number: WO2024149639A1
Application number: PCT/EP2024/050052
Authority: WO
Inventors: Jeffrey Scott HART; Haifeng Wang
Original assignee: Koninklijke Philips NV
Current assignee: Koninklijke Philips NV
Priority date: 2023-01-11
Filing date: 2024-01-03
Publication date: 2024-07-18
Anticipated expiration: 2025-07-11
Also published as: CN120603658A; EP4648908A1

Abstract

A transducer element (211 A) includes a plurality of layers, at least one signal connection, and a first outer ground electrode and a second outer ground electrode. The second piezoelectric layer (362) is adjacent to and physically separate from the first piezoelectric layer (361). The second outer ground electrode is physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

Description

ADJUSTABLE TRANSDUCER ELEMENTS

BACKGROUND

[0001] Conventional ultrasound transducers typically include transducer elements with an acoustic stack, a flex circuit, and a backing. Conventional ultrasound transducers typically include a single piezoelectric layer, matching layers and inner acoustic layers, and the backing. The matching improves transmissivity and shapes the resonance to tailor the resonance to an intended frequency and appropriate bandwidth. The inner acoustic layers can include dematching layers that have an impedance attached to the piezoelectric layer and are used to create a reflective interface rather than to enhance transmission. Bandwidth and sensitivity are optimized for each application by use of various numbers and types of matching layers, piezoelectric materials, dematching layers, and backings. As an example, a transducer element which achieves state of the art performance today may include a dematched single crystal and two matching layers. Signal and redundant ground connections may be separated by isolation cuts into the acoustic stack. The flex circuit provides the electrical interconnect for each other element.

[0002] The use of multilayer piezoelectric transducer elements has been known as a solution to reduce element electrical impedance and drive voltage requirements. However, the use of multilayer piezoelectric transducer elements is not commonplace due to the added complexity and poor trade-offs compared to other methods. The multilayer piezoelectric transducer elements that have been explored do not include independently controllable ground connections, and are not optimized simultaneously for sensitivity and bandwidth, and instead trade off between sensitivity and bandwidth.

SUMMARY

[0003] According to an aspect of the present disclosure, a transducer element includes a plurality of layers, at least one signal connection, and a first outer ground electrode and a second outer ground electrode. The plurality of layers include a first piezoelectric layer and a second piezoelectric layer adjacent to and physically separate from the first piezoelectric layer. The second outer ground electrode is physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

[0004] According to another aspect of the present disclosure, an ultrasound probe includes a plurality of transducer elements. Each of the transducer elements includes a plurality of layers, at least one signal connection, and a first outer ground electrode and a second outer ground electrode. The plurality of layers include a first piezoelectric layer and a second piezoelectric layer adjacent to and physically separate from the first piezoelectric layer. The second outer ground electrode is physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

[0005] According to another aspect of the present disclosure, an ultrasound system includes an ultrasound base station and an ultrasound probe. The ultrasound probe includes a plurality of transducer elements. Each of the transducer elements includes a plurality of layers, at least one signal connection, and a first outer ground electrode and a second outer ground electrode. The plurality of layers include a first piezoelectric layer and a second piezoelectric layer adjacent to and physically separate from the first piezoelectric layer. The second outer ground electrode is physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The example embodiments are best understood from the following detailed description when read with the accompanying drawing figures. It is emphasized that the various features are not necessarily drawn to scale. In fact, the dimensions may be arbitrarily increased or decreased for clarity of discussion. Wherever applicable and practical, like reference numerals refer to like elements.

[0007] FIG. 1 illustrates a system for adjustable transducer elements, in accordance with a representative embodiment.

[0008] FIG. 2A illustrates an ultrasound probe for adjustable transducer elements, in accordance with a representative embodiment.

[0009] FIG. 2B illustrates another ultrasound probe for adjustable transducer elements, in accordance with a representative embodiment.

[0010] FIG. 3 A illustrates an adjustable transducer element, in accordance with a representative embodiment. [0011] FIG. 3B illustrates a switching system for an adjustable transducer element, in accordance with a representative embodiment.

[0012] FIG. 4 illustrates a method for adjustable transducer elements, in accordance with a representative embodiment.

[0013] FIG. 5A illustrates frequency distributions for adjustable transducer elements, in accordance with a representative embodiment.

[0014] FIG. 5B illustrates element electrical impedance, in accordance with a representative embodiment.

[0015] FIG. 6 illustrates a computer system, on which a method for adjustable transducer elements is implemented, in accordance with another representative embodiment.

DETAILED DESCRIPTION

[0016] In the following detailed description, for the purposes of explanation and not limitation, representative embodiments disclosing specific details are set forth in order to provide a thorough understanding of embodiments according to the present teachings. However, other embodiments consistent with the present disclosure that depart from specific details disclosed herein remain within the scope of the appended claims. Descriptions of known systems, devices, materials, methods of operation and methods of manufacture may be omitted so as to avoid obscuring the description of the representative embodiments. Nonetheless, systems, devices, materials and methods that are within the purview of one of ordinary skill in the art are within the scope of the present teachings and may be used in accordance with the representative embodiments. It is to be understood that the terminology used herein is for purposes of describing particular embodiments only and is not intended to be limiting. Definitions and explanations for terms herein are in addition to the technical and scientific meanings of the terms as commonly understood and accepted in the technical field of the present teachings.

[0017] It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements or components, these elements or components should not be limited by these terms. These terms are only used to distinguish one element or component from another element or component. Thus, a first element or component discussed below could be termed a second element or component without departing from the teachings of the inventive concept. [0018] As used in the specification and appended claims, the singular forms of terms ‘a’, ‘an’ and ‘the’ are intended to include both singular and plural forms, unless the context clearly dictates otherwise. Additionally, the terms "comprises", and/or "comprising," and/or similar terms when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0019] Unless otherwise noted, when an element or component is said to be “connected to”, “coupled to”, or “adjacent to” another element or component, it will be understood that the element or component can be directly connected or coupled to the other element or component, or intervening elements or components may be present. That is, these and similar terms encompass cases where one or more intermediate elements or components may be employed to connect two elements or components. However, when an element or component is said to be “directly connected” to another element or component, this encompasses only cases where the two elements or components are connected to each other without any intermediate or intervening elements or components.

[0020] The present disclosure, through one or more of its various aspects, embodiments and/or specific features or sub-components, is thus intended to bring out one or more of the advantages as specifically noted below.

[0021] As described herein, a multilayer piezoelectric element is provided with independently controllable ground connections along with signal connections. The multilayer piezoelectric element described herein allows for increased performance of multiple transducer aspects including bandwidth, sensitivity, electrical impedance, and low voltage capability, all leading to improved clinical utility for a given transducer.

[0022] The fundamental limits on the resonance of a single piezoelectric element are overcome using the teachings herein. Independently controllable ground/return connections used in the transducer architecture described herein may unlock additional degrees of freedom in transducer design. This design freedom may be optimized for a variety of system parameters and modes of operation including low voltage transmit, transmission/reception optimization in harmonic imaging, and further separation of penetration and resolution settings increasing clinical utility of a single transducer.

[0023] FIG. 1 illustrates a system 100 for adjustable transducer elements, in accordance with a representative embodiment.

[0024] The system 100 in FIG. 1 is a system for adjustable transducer elements and includes components that are typically provided together, though not necessarily directly connected together. The system 100 includes an ultrasound probe 110, an ultrasound base 120, and a display 180.

[0025] The ultrasound probe 110 includes a transducer array 111, and the transducer array 111 includes a plurality of transducer elements including a first transducer element 1111, a second transducer element 1112 through an Xth transducer element 11 IX. The transducer array I l l is used to form apertures when the ultrasound probe 110 transmits ultrasound waves and receives echoes of the ultrasound waves. As an example, the transducer array 111 may include, for example, 192 x 2 transducer elements, for a total of 384 transducer elements. The ultrasound probe 110 may be configured to connect to a digital cable as compared to a conventional analog coaxial cable.

[0026] The ultrasound base 120 may be implemented as a cart with a workstation, or as a mobile device such as a tablet computer or smartphone with an ultrasound control application installed thereon. The ultrasound base 120 includes a first interface 121, a second interface 122, a user interface 123, and a controller 150. The controller 150 includes at least a memory 151 that stores instructions and a processor 152 that executes the instructions. A computer that can be used to implement the ultrasound base 120 is depicted in FIG. 6, though an ultrasound base 120 may include more or fewer elements than depicted in FIG. 1 or FIG. 6.

[0027] The first interface 121 interfaces the ultrasound base 120 to the ultrasound probe 110.

The second interface 122 interfaces the ultrasound base 120 to the display 180. The first interface 121 and the second interface may include ports, wireless antennas, or other types of receiver circuitry that connect the ultrasound base 120 to other electronic elements. The user interface 123 may comprise an interactive interface such as a touchscreen, buttons, keys, a mouse, a microphone, a speaker, a display separate from the display 180, or other elements that users can use to interact with the ultrasound base 120 such as to enter instructions and receive output. The user interface may comprise a system console comprising a graphical user interface 181, and the user interface may be configured to control one or more switches to connect either or both of a first outer ground electrode and a second outer ground electrode.

[0028] The controller 150 may perform some of the operations described herein directly and may implement other operations described herein indirectly. For example, the controller 150 may indirectly control operations such as by generating and transmitting content to be displayed on the display 180. The controller 150 may directly control other operations such as logical operations performed by the processor 152 executing instructions from the memory 151 based on input received from electronic elements and/or users via the interfaces. Accordingly, the processes implemented by the controller 150 when the processor 152 executes instructions from the memory 151 may include steps not directly performed by the controller 150. In some embodiments, multiple different elements of the system 100 in FIG. 1 may include a controller such as the controller 150.

[0029] The display 180 may be local to the controller 150 or may be remotely connected to the controller 150. The display 180 may be connected to the controller 150 via a local wired interface such as an Ethernet cable or via a local wireless interface such as a Wi-Fi connection. The display 180 may be interfaced with other user input devices by which users can input instructions, including mouses, keyboards, thumbwheels and so on. The display 180 may be a monitor such as a computer monitor, a display on a mobile device, an augmented reality display, a television, an electronic whiteboard, or another screen configured to display electronic imagery. The display 180 may also include one or more input interface(s) such as those noted above that may connect to other elements or components, as well as an interactive touch screen configured to display prompts to users and collect touch input from users.

[0030] FIG. 2A illustrates an ultrasound probe for adjustable transducer elements, in accordance with a representative embodiment.

[0031] In FIG. 2 A, an ultrasound probe 210A includes a transducer 211 A, a controller 215 A, switches 216A, a first transducer element 2111 A, a second transducer element 2112A through the Xth transducer element 211XA, a lens 214A and a user interface 223 A.

[0032] In FIG. 2A, the controller 215 A is provided as an element of the ultrasound probe 210A. The controller 215 A may comprise an application-specific integrated circuit or a combination of a memory that stores instructions and a processor that executes the instructions. The controller 215 A may control operations of the ultrasound probe 210A, such as switching of the switches 216A based on what type of anatomy the ultrasound probe 210A is being used to image. Additionally, the switches 216A are shown to be separate from the transducer elements of the transducer 211 A, but the switches 216A may be provided on a per electrode basis of each element of the transducer 211 A.

[0033] FIG. 2B illustrates another ultrasound probe for adjustable transducer elements, in accordance with a representative embodiment.

[0034] In FIG. 2B, an ultrasound probe 21 OB includes a transducer 21 IB, a controller 215B, switches 216B, a first transducer element 211 IB, a second transducer element 2112B through the Xth transducer element 211XB, a lens 214B and a user interface 223B.

[0035] In FIG. 2A, the controller 215B is provided external to the ultrasound probe 210A, and may be provided in an ultrasound base such as the ultrasound base 120 in FIG. 1 for example. The controller 215B may comprise an application-specific integrated circuit or a combination of a memory that stores instructions and a processor that executes the instructions. The controller 215B may control operations of the ultrasound probe 210B, such as switching of the switches 216B based on type of anatomy the ultrasound probe 210B is being used to image. Additionally, the switches 216B are shown to be separate from the transducer elements of the transducer 21 IB, but the switches 216B may be provided on a per electrode basis of each element of the transducer 21 IB.

[0036] FIG. 3 A illustrates an adjustable transducer element, in accordance with a representative embodiment. The adjustable transducer element of FIG. 3 A may correspond to the previously indicated transducer 211 A or transducer 21 IB.

[0037] The transducer element in FIG. 3 A is a non-symmetric multi-layer stack with independent ground/return. The transducer element in FIG. 3 A includes a first element signal connection 311 and a second element signal connection 312, a first ground connection 341, a second ground connection 342, a third ground connection 343, a fourth ground connection 344, one or more matching layer(s) 351, a first piezoelectric layer 361, a second piezoelectric layer 362, and one or more inner layer(s) 371. The first element signal connection 311 is persistently connected to the second element signal connection 312. The first ground connection 341 is the bottom surface of the inner layer(s) 371 and interfaces with other transducer components as a flexible circuit. The third ground connection 343 is the outer ground electrode of the first piezoelectric layer 361. The first ground connection 341 and the third ground connection 343 may be electrically connected through bulk conductivity or via structures through the inner layer(s) 371. The fourth ground connection 344 is the outer ground electrode of the second piezoelectric layer 362, and may be connected to the second ground connection 342 persistently. [0038] FIG. 3 A illustrates the interconnect structure for the transducer element. Voltages are applied to the first piezoelectric layer 361 and the second piezoelectric layer 362 through the first element signal connection 311 and the second element signal connection 312, respectively. The inner layer(s) 371 are conductive and may comprise tungsten carbide.

[0039] In FIG. 3A, the transducer element includes the first piezoelectric layer 361 and the second piezoelectric layer 362 and two outer ground electrodes including the second ground connection 342 and the third ground connection 343. The two outer ground connections are not shorted together and are not redundant. The piezoelectric layers may be of equal thickness or may be skewed to further optimize the resonance structure as shown in FIG. 3 A. One or both piezoelectric layers may comprise a composite material. For example, the second piezoelectric layer 362 may comprise a composite material to optimize transmission in the active configuration of the first piezoelectric layer 361. A composite material used as a piezoelectric layer may function as a matching layer when not active. A preferred off state condition of the ground electrode may be determined during development so as to configure the piezoelectric layers to be shorted to the signal, to be floating, or to be connected to an arbitrary level. In some embodiments, a piezoelectric layer may comprise a ceramic material or crystal material.

[0040] The piezoelectric layers of the transducer element in FIG. 3 A are broken into two discrete layers. The ground or the signal return electrodes are managed independently so as to be switched on and off independently. Each piezoelectric layer may be selectively connectable by a switch to ground potential. When both ground connections are connected by the switch so that the corresponding piezoelectric layers are both active so as to oscillate, the effective thickness of the overall piezoelectric structure is increased and results in a lower frequency response. Connection of both ground connections also results in a higher electrical impedance which may match better to the electrical impedance of the ultrasound system, either in transmission mode or receive mode. Conversely, if only one of the piezoelectric layers in FIG. 3 A is connected to ground through the switch, the disconnected piezoelectric layer is effectively left open and acts as a non-active layer so that the effective thickness of the overall piezoelectric structure is lowered and results in a higher frequency resonance. Connection of only one of the piezoelectric layers in FIG. 3 A also results in a lower electrical impedance which may match better to the electrical impedance of ultrasound system, either in transmission mode or receive mode. In other words, a lower active thickness of the overall piezoelectric structure corresponds to a higher frequency response, and vice versa. A lower frequency provides greater penetration depth and the higher frequency provides better resolution. The mode of the ultrasound probe with an array of transducer elements as in FIG. 3 A may be controlled through the ultrasound base 120 in FIG. 1, and an array of corresponding switches may be set in response to a selection of mode.

[0041] As set forth above, the transducer element in FIG. 3 A includes a plurality of layers including the first piezoelectric layer 361 and the second piezoelectric layer 362 adjacent to and physically separate from the first piezoelectric layer; the first element signal connection 311 and the second element signal connection 312; and the ground connection 341 as a first outer ground electrode and the second ground connection 342 as a second outer ground electrode. The second outer ground electrode is physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable. Each transducer element in a transducer array such as the transducer array 111 may be configured in the same or a similar manner as the transducer element in FIG. 3 A.

[0042] In FIG. 3A, the first piezoelectric layer 361 has a different thickness than the second piezoelectric layer 362. For example, the first piezoelectric layer 361 may be twice as thick as the second piezoelectric layer 362, so that relative thicknesses provides by the piezoelectric layers alone or combined may vary between a base thickness of the second piezoelectric layer 362, a base thickness of the first piezoelectric layer 361, or the combined base thicknesses of the piezoelectric layers. Layer thicknesses may be chosen to define a particular resonance and may be tailored to a degree. Frequency spectra of the transducer element in FIG. 3 A may vary based on variations in configurations of the first outer ground electrode and the second outer ground electrode. The first piezoelectric layer 361 and the second piezoelectric layer 362 may have differing thicknesses optimized for a resonance structure of the transducer element with different electrical impedances.

[0043] In FIG. 3 A, two piezoelectric layers are shown for the transducer element. However, transducer elements in a transducer array may include more than two piezoelectric layers consistent with the teachings herein. More than two piezoelectric layers may provide a larger range of potential imaging modes and increased refinement of frequency spectra used for such imaging modes.

[0044] FIG. 3B illustrates a switching system for an adjustable transducer element, in accordance with a representative embodiment. [0045] In FIG. 3B, a first set of switches 381 is shown on the right and a second set of switches 382 is shown on the left. The first set of switches 381 and the second set of switches 382 are configured to switchably disconnect and connect individual ground connections of an adjustable transducer element, as described with respect to FIG. 3 A. The first set of switches 381 and the second set of switches 382 may be independently operable and/or may be operable as a group. The connections el, e2 and e3 are connections to different electrodes for different layers of a transducer element, and connection of the first set of switches 381 and/or the second set of switches 382 will connect various configurations of electrodes based on the mode of operation for the ultrasound probe 110. Frequency spectra of the transducer element in FIG. 3B may vary based on variations in configurations of the first outer ground electrode and the second outer ground electrode, and this may be due to either or both of the thicknesses of the piezoelectric layers and the configurations of the switches and the corresponding configurations of the first outer ground electrode and the second outer ground electrode.

[0046] FIG. 3B illustrates an ability to independently control each piezoelectric layer of a transducer element using switches which connect to ground connections. The ultrasound probe 110 or the ultrasound base 120 in FIG. 1 may include a user interface which enables a user to select a mode for the ultrasound probe, and the selection of the mode may automatically result in a configuration of the first set of switches 381 and the second set of switches 382. The ultrasound probe 110 may be programmed to connect the first set of switches 381 and the second set of switches 382 for each transducer element based on the mode in which the ultrasound probe 110 is being used. The modes may correspond to preset configurations of the switches so that the ultrasound probe 110 varies in operation based on the type of imaging being performed.

[0047] FIG. 4 illustrates a method for adjustable transducer elements, in accordance with a representative embodiment.

[0048] In FIG. 4, a mode is set at S410. The mode may be set at S410 automatically or by an operator entering an instruction into a user interface. The user interface may be provided on the ultrasound probe 110 or the ultrasound base 120 in FIG. 1.

[0049] At S420, switches are controlled. For example, the switches of the ultrasound probe 110 may be controlled based on the mode, to connect either or both piezoelectric layers to ground electrodes. In embodiments in which more than two piezoelectric layers are implemented for each transducer element, the switches may be switched into more than three configurations, particularly when any two or more piezoelectric layers have different thicknesses such that more than three different electrical impedances may be configured. The switches may be controlled for each different transducer element of the ultrasound probe 110. In some embodiments, the switches may be controlled for a subset of the transducer elements, such as when some transducer elements are not to be used in a mode.

[0050] At S430, an ultrasound probe transmits an ultrasound signal via a transducer array, and at S440, the ultrasound probe receives echoes of the ultrasound signal via the transducer array.

[0051] At S450, the received echoes may be digitized, such as by analog-to-digital converters in the ultrasound probe. In some embodiments in which output of the ultrasound probe to an ultrasound base is not digitized, S450 may be optional.

[0052] At S460, the digitized signals are transmitted via cable, such as from the ultrasound probe 110 to the ultrasound base 120 in FIG. 1.

[0053] At S470, the transmitted signals are received, stored and displayed. In embodiments in which output of the ultrasound probe is not digitizes, digitization may be performed at the display.

[0054] At S480, a determination is made as to whether the echoes received at S440 are the last echoes expected. If additional transmissions and echoes are expected (S480 = No), the method returns to S430, and otherwise (S480 = Yes), the method ends at S490.

[0055] FIG. 5A illustrates frequency distributions for adjustable transducer elements, in accordance with a representative embodiment.

[0056] The spectra shown in FIG. 5A are hypothetical spectra from each connection configuration with frequency shifts based on the transducer element in FIG. 3 A. In FIG. 5A, the spectra when both the first ground connection 341 and the second ground connection 342 are connected is labelled as “1” and is the leftmost spectra. The spectra when only the first ground connection 341 is connected is labelled as “2” and is the center spectra. The spectra when only the second ground connection 342 is connected is labelled as “3” and is the rightmost spectra. In addition FIG. 5B shows the corresponding element electrical impedance for the respective cases shown in FIG. 5 A. FIG. 5B illustrates element electrical impedance, in accordance with a representative embodiment.

[0057] FIG. 6 illustrates a computer system, on which a method for adjustable transducer elements is implemented, in accordance with another representative embodiment. [0058] Referring to FIG.6, the computer system 600 includes a set of software instructions that can be executed to cause the computer system 600 to perform any of the methods or computer- based functions disclosed herein. The computer system 600 may operate as a standalone device or may be connected, for example, using a network 601, to other computer systems or peripheral devices. In embodiments, a computer system 600 performs logical processing based on digital signals received via an analog-to-digital converter.

[0059] In a networked deployment, the computer system 600 operates in the capacity of a server or as a client user computer in a server-client user network environment, or as a peer computer system in a peer-to-peer (or distributed) network environment. The computer system 600 can also be implemented as or incorporated into various devices, such as the ultrasound base 120, a workstation that includes a controller, a stationary computer, a mobile computer, a personal computer (PC), a laptop computer, a tablet computer, or any other machine capable of executing a set of software instructions (sequential or otherwise) that specify actions to be taken by that machine. The computer system 600 can be incorporated as or in a device that in turn is in an integrated system that includes additional devices. In an embodiment, the computer system 600 can be implemented using electronic devices that provide voice, video or data communication. Further, while the computer system 600 is illustrated in the singular, the term “system” shall also be taken to include any collection of systems or sub-systems that individually or jointly execute a set, or multiple sets, of software instructions to perform one or more computer functions.

[0060] As illustrated in FIG. 6, the computer system 600 includes a processor 610. The processor 610 may be considered a representative example of a processor of a controller and executes instructions to implement some or all aspects of methods and processes described herein. The processor 610 is tangible and non-transitory. As used herein, the term “non- transitory” is to be interpreted not as an eternal characteristic of a state, but as a characteristic of a state that will last for a period. The term “non-transitory” specifically disavows fleeting characteristics such as characteristics of a carrier wave or signal or other forms that exist only transitorily in any place at any time. The processor 610 is an article of manufacture and/or a machine component. The processor 610 is configured to execute software instructions to perform functions as described in the various embodiments herein. The processor 610 may be a general- purpose processor or may be part of an application specific integrated circuit (ASIC). The processor 610 may also be a microprocessor, a microcomputer, a processor chip, a controller, a microcontroller, a digital signal processor (DSP), a state machine, or a programmable logic device. The processor 610 may also be a logical circuit, including a programmable gate array (PGA), such as a field programmable gate array (FPGA), or another type of circuit that includes discrete gate and/or transistor logic. The processor 610 may be a central processing unit (CPU), a graphics processing unit (GPU), or both. Additionally, any processor described herein may include multiple processors, parallel processors, or both. Multiple processors may be included in, or coupled to, a single device or multiple devices.

[0061] The term “processor” as used herein encompasses an electronic component able to execute a program or machine executable instruction. References to a computing device comprising “a processor” should be interpreted to include more than one processor or processing core, as in a multi-core processor. A processor may also refer to a collection of processors within a single computer system or distributed among multiple computer systems. The term computing device should also be interpreted to include a collection or network of computing devices each including a processor or processors. Programs have software instructions performed by one or multiple processors that may be within the same computing device or which may be distributed across multiple computing devices.

[0062] The computer system 600 further includes a main memory 620 and a static memory 630, where memories in the computer system 600 communicate with each other and the processor 610 via a bus 608. Either or both of the main memory 620 and the static memory 630 may be considered representative examples of a memory of a controller, and store instructions used to implement some or all aspects of methods and processes described herein. Memories described herein are tangible storage mediums for storing data and executable software instructions and are non-transitory during the time software instructions are stored therein. As used herein, the term “non-transitory” is to be interpreted not as an eternal characteristic of a state, but as a characteristic of a state that will last for a period. The term “non-transitory” specifically disavows fleeting characteristics such as characteristics of a carrier wave or signal or other forms that exist only transitorily in any place at any time. The main memory 620 and the static memory 630 are articles of manufacture and/or machine components. The main memory 620 and the static memory 630 are computer-readable mediums from which data and executable software instructions can be read by a computer (e.g., the processor 610). Each of the main memory 620 and the static memory 630 may be implemented as one or more of random access memory (RAM), read only memory (ROM), flash memory, electrically programmable read only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, a hard disk, a removable disk, tape, compact disk read only memory (CD-ROM), digital versatile disk (DVD), floppy disk, blu-ray disk, or any other form of storage medium known in the art. The memories may be volatile or non-volatile, secure and/or encrypted, unsecure and/or unencrypted. [0063] “Memory” is an example of a computer-readable storage medium. Computer memory is any memory which is directly accessible to a processor. Examples of computer memory include, but are not limited to RAM memory, registers, and register files. References to “computer memory” or “memory” should be interpreted as possibly being multiple memories. The memory may for instance be multiple memories within the same computer system. The memory may also be multiple memories distributed amongst multiple computer systems or computing devices. [0064] As shown, the computer system 600 further includes a video display unit 650, such as a liquid crystal display (LCD), an organic light emitting diode (OLED), a flat panel display, a solid-state display, or a cathode ray tube (CRT), for example. Additionally, the computer system 600 includes an input device 660, such as a keyboard/virtual keyboard or touch-sensitive input screen or speech input with speech recognition, and a cursor control device 670, such as a mouse or touch-sensitive input screen or pad. The computer system 600 also optionally includes a disk drive unit 680, a signal generation device 690, such as a speaker or remote control, and/or a network interface device 640.

[0065] In an embodiment, as depicted in FIG. 6, the disk drive unit 680 includes a computer- readable medium 682 in which one or more sets of software instructions 684 (software) are embedded. The sets of software instructions 684 are read from the computer-readable medium 682 to be executed by the processor 610. Further, the software instructions 684, when executed by the processor 610, perform one or more steps of the methods and processes as described herein. In an embodiment, the software instructions 684 reside all or in part within the main memory 620, the static memory 630 and/or the processor 610 during execution by the computer system 600. Further, the computer-readable medium 682 may include software instructions 684 or receive and execute software instructions 684 responsive to a propagated signal, so that a device connected to a network 601 communicates voice, video or data over the network 601. The software instructions 684 may be transmitted or received over the network 601 via the network interface device 640. [0066] In an embodiment, dedicated hardware implementations, such as application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), programmable logic arrays and other hardware components, are constructed to implement one or more of the methods described herein. One or more embodiments described herein may implement functions using two or more specific interconnected hardware modules or devices with related control and data signals that can be communicated between and through the modules. Accordingly, the present disclosure encompasses software, firmware, and hardware implementations. Nothing in the present application should be interpreted as being implemented or implementable solely with software and not hardware such as a tangible non-transitory processor and/or memory.

[0067] In accordance with various embodiments of the present disclosure, the methods described herein may be implemented using a hardware computer system that executes software programs. Further, in an exemplary, non-limited embodiment, implementations can include distributed processing, component/object distributed processing, and parallel processing. Virtual computer system processing may implement one or more of the methods or functionalities as described herein, and a processor described herein may be used to support a virtual processing environment.

[0068] Accordingly, adjustable transducer elements provides a multilayer piezoelectric element with independently controllable ground connections along with signal connections. The multilayer piezoelectric element described herein allows for increased performance of multiple transducer aspects including bandwidth, sensitivity, electrical impedance, and low voltage capability, all leading to improved clinical utility for a given transducer.

[0069] Although adjustable transducer elements has been described with reference to several exemplary embodiments, it is understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of adjustable transducer elements in its aspects. Although adjustable transducer elements has been described with reference to particular means, materials and embodiments, adjustable transducer elements is not intended to be limited to the particulars disclosed; rather adjustable transducer elements extends to all functionally equivalent structures, methods, and uses such as are within the scope of the appended claims.

[0070] The illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The illustrations are not intended to serve as a complete description of all of the elements and features of the disclosure described herein. Many other embodiments may be apparent to those of skill in the art upon reviewing the disclosure. Other embodiments may be utilized and derived from the disclosure, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. Additionally, the illustrations are merely representational and may not be drawn to scale. Certain proportions within the illustrations may be exaggerated, while other proportions may be minimized. Accordingly, the disclosure and the figures are to be regarded as illustrative rather than restrictive.

[0071] One or more embodiments of the disclosure may be referred to herein, individually and/or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any particular invention or inventive concept. Moreover, although specific embodiments have been illustrated and described herein, it should be appreciated that any subsequent arrangement designed to achieve the same or similar purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all subsequent adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the description.

[0072] The Abstract of the Disclosure is provided to comply with 37 C.F.R. § 1.72(b) and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, various features may be grouped together or described in a single embodiment for the purpose of streamlining the disclosure. This disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter may be directed to less than all of the features of any of the disclosed embodiments. Thus, the following claims are incorporated into the Detailed Description, with each claim standing on its own as defining separately claimed subject matter.

[0073] The preceding description of the disclosed embodiments is provided to enable any person skilled in the art to practice the concepts described in the present disclosure. As such, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the true spirit and scope of the present disclosure. Thus, to the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents and shall not be restricted or limited by the foregoing detailed description.

Claims

CLAIMS:

1. A transducer element (211 A), comprising: a plurality of layers including a first piezoelectric layer (361) and a second piezoelectric layer (362) adjacent to and physically separate from the first piezoelectric layer (361); at least one signal connection (311); and a first outer ground electrode (341) and a second outer ground electrode (342) physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

2. The transducer element (211 A) of claim 1, wherein frequency spectra of the transducer element (211 A) vary based on variations in configurations of the first outer ground electrode and the second outer ground electrode.

3. The transducer element (211 A) of claim 2, further comprising: a switch configured to connect either or both of the first outer ground electrode and the second outer ground electrode to vary the frequency spectra of the transducer element (211 A).

4. The transducer element (211 A) of claim 3, wherein the switch is controlled to connect to either or both of the first outer ground electrode and the second outer ground electrode via a user interface (123).

5. The transducer element (211 A) of claim 1, wherein the first piezoelectric layer (361) and the second piezoelectric layer (362) have differing thicknesses optimized for a resonance structure of the transducer element (211 A) with different electrical impedances.

6. The transducer element (211 A) of claim 1, wherein at least one of the first piezoelectric layer (361) or the second piezoelectric layer (362) comprises a composite material.

7. The transducer element (211 A) of claim 1, wherein the transducer element (211 A) is a component of an ultrasound probe (110) which is configured to connect to a digital cable.

8. An ultrasound probe (110), comprising: a plurality of transducer elements (211 A), wherein each of the transducer elements (211 A) comprises: a plurality of layers including a first piezoelectric layer (361) and a second piezoelectric layer (362) adjacent to and physically separate from the first piezoelectric layer (361); at least one signal connection; and a first outer ground electrode and a second outer ground electrode physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

9. The ultrasound probe (110) of claim 8, wherein frequency spectra of each transducer element (211 A) vary based on variations in configurations of the first outer ground electrode and the second outer ground electrode of the transducer element (211 A).

10. The ultrasound probe (110) of claim 9, wherein each transducer element (211 A) further comprises: a switch configured to connect either or both of the first outer ground electrode and the second outer ground electrode to vary the frequency spectra of the transducer element (211 A), wherein the switch is controlled to connect to either or both of the first outer ground electrode and the second outer ground electrode via a user interface (123).

11. The ultrasound probe (110) of claim 8, wherein the first piezoelectric layer (361) and the second piezoelectric layer (362) of each transducer element (211 A) have differing thicknesses optimized for a resonance structure of the ultrasound probe (110) having different electrical impedances.

12. The ultrasound probe (110) of claim 8, wherein at least one of the first piezoelectric layer (361) or the second piezoelectric layer (362) of each transducer element (211 A) comprises a composite material.

13. The ultrasound probe (110) of claim 8, wherein each transducer element (211 A) is configured to connect to a digital cable.

14. An ultrasound system (100), comprising: an ultrasound base (120) station; and an ultrasound probe (110), wherein the ultrasound probe (110) comprises: a plurality of transducer elements (211 A), wherein each of the transducer elements (211 A) comprises: a plurality of layers including a first piezoelectric layer (361) and a second piezoelectric layer (362) adjacent to and physically separate from the first piezoelectric layer (361); at least one signal connection; and a first outer ground electrode and a second outer ground electrode physically separated from the first outer ground electrode such that the first outer ground electrode and the second outer ground electrode are independently controllable.

15. The ultrasound system (100) of claim 14, wherein frequency spectra of each transducer element (211 A) vary based on variations in configurations of the first outer ground electrode and the second outer ground electrode of the transducer element (211 A).

16. The ultrasound system (100) of claim 15, further comprising: a user interface (123), wherein each transducer element (211 A) further comprises: a switch configured to connect either or both of the first outer ground electrode and the second outer ground electrode to vary the frequency spectra of the transducer element (211 A), wherein the switch is controlled to connect to either or both of the first outer ground electrode and the second outer ground electrode via the user interface (123).

17. The ultrasound system (100) of claim 16, wherein the user interface (123) comprises a system (100) console comprising a graphical user interface (123).

18. The ultrasound system (100) of claim 14, wherein the first piezoelectric layer (361) and the second piezoelectric layer (362) of each transducer element (211 A) have differing thicknesses optimized for a resonance structure of the ultrasound probe (110) with different electrical impedances.

19. The ultrasound system (100) of claim 14, wherein at least one of the first piezoelectric layer (361) or the second piezoelectric layer (362) of each transducer element (211 A) comprises a composite material.

20. The ultrasound system (100) of claim 14, wherein each transducer element (211 A) is configured to connect to a digital cable.